CI integration

Integrating Earthly into your CI is simply a matter of automating the same steps you would use for your local installation. In this guide, we will walk through this process.

Step 1: Ensure pre-requisites are available

Docker and Git

The first step is to ensure that Earthly's pre-requisites, Docker and Git, are available. On many CI systems both of these already exist in the default base image or environment. Refer to your provider's documentation.

Vendors known to include these dependencies:

  • CircleCI image ubuntu-1604:201903-01

  • GitHub actions ubuntu-latest

  • Travis dist xenial

  • GitLab image docker:git with service docker:dind added.

  • Azure DevOps vmImage Ubuntu-16.04

  • AWS CodeBuild image aws/codebuild/amazonlinux2-x86_64-standard:3.0

Privileged mode

In addition to Docker and Git, Earthly also requires privileged mode as it executes container builds under the hood. In most linux-based CI environments, this is readily available and no special setting is necessary. GitLab CI requires using a compatible runner (eg Docker) and explicitly enabling privileged mode.

Step 2: Install earth command

The next step is to install the earth command. For this, you need to run the command:

sudo /bin/sh -c 'wget https://github.com/earthly/earthly/releases/download/v0.3.11/earth-linux-amd64 -O /usr/local/bin/earth && chmod +x /usr/local/bin/earth'

Note

The above command installs a specific version of earth. It is not advisable to always download the very latest, as any possible backwards incompatible changes of Earthly (rare) could cause your builds to fail unexpectedly. Pinning to a specific version, as shown here, is recommended.

In certain CI environments, such as Jenkins, where you have access to the host, it may be more convenient to install Earthly on the host in advance, so that your builds do not need to download earth every time they run.

Step 3: Configure earth

Depending on your needs, you may need to ensure that Git has authenticated access and / or that Docker is logged in so that it has access to private repositories.

To authenticate Git, you may either use SSH-based authentication, or username-password-based authentication. See the Authentication page for more information. In case you don't need any Git authentication, you might want to force all GitHub URLs to be transformed to https://github.com/... instead of git@github.com:.... For this, you can add an environment variable to configure this behavior:

export GIT_URL_INSTEAD_OF="https://github.com/=git@github.com:"

The way you configure environment variables in your CI will vary.

To log in Docker, simply run

docker login --username '<username>' --password '<password>'

Note

Make sure that secrets (like <password> above) are not exposed in plain text. You may need to configure an environment variable with your CI vendor.

Step 4: (Optional) Force or disable color output

The CLI earth automatically detects the presence of a TTY for the purpose of deciding whether to use colorized output or not. In some CI environments, this kind of detection is not enough in order to infer support for colorized output. However, two environment variables can be used to either disable or force it:

  • NO_COLOR=1 disables the use of color.

  • FORCE_COLOR=1 forces the use of color.

The following environments are known to require additional settings:

  • GitHub Actions: requires FORCE_COLOR=1

  • Jenkins: requires NO_COLOR=1

Step 5: Run the build

earth +target-name

If you would like to enable pushing Docker images to registries and also running RUN --push commands, you might use

earth --push +target-name

If you need to pass secrets to the Earthly build, you might also use the --secret flag, mentioning the env var where the secret is kept.

earth --secret SOME_SECRET_ENV_VAR +target-name

For more information see the earth command reference.

Complete examples

A couple of build examples are available for